Interface Computer for a Stage Lighting System

ABSTRACT

A stage lighting system with a digital and analog part. The digital part is used to form the image, which can be, for example, a full brightness image. The analog part is used to dim the image, and to carry out failsafe operation. If an error occurs in the digital part, then the analog part prevents the image from being shown.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims benefit of the priority of U.S. Provisional Application Ser. No. 60/493,532 filed Aug. 7, 2003 and entitled “Interface Computer for a Stage Lighting System”.

BACKGROUND

Stage lighting control can be extremely complex. A control console can be used to control a number of different lights which collectively form a show. Each of the lights can be controlled to move in different ways and to project different effects including shapes for light, video effects, color, and other things. Digital techniques have enabled stage lights to produce many different effects, however they have also produced complexities. As the capabilities increase, the control becomes more complex.

SUMMARY

The present system teaches a lighting control system in which a computer or other interface device is controlled by a lighting control console, and used to control an external controlled light which may be a projector or the like. The external controlled light can be controlled according to many different complex effects.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects will now be described in detail with reference to the accompanying drawings, in which:

FIG. 1 shows a basic block diagram of the system;

FIG. 2 shows a block diagram of the interface board which is used;

FIG. 3 shows a flowchart of operation;

FIG. 4 shows more detail about the interface card.

DETAILED DESCRIPTION

FIG. 1 shows a basic block diagram of the present system. In the FIG. 1 embodiment, a lighting control console 100, which may be an ICON™ console is used to control a number of controllable lights collectively forming a lighting show. An output line 101 may be connected to a “distro” 103, that controls lights 102 and 104 of conventional types. These may be lights that are available from, for example, Light and Sound Design Ltd., or from other comparable vendors. These lights typically have certain functionality built therein.

The device of the present system also includes a computer based light 110 which runs software to carry out the functions commanded by the console. The computer light may be output to an interface card 115 which may drive lighting projector 120. For example, this may drive a DMD type projector. The projector 120 projects information as commanded by the computer 110.

Understandably, the computer 110 must carry out certain relatively complicated functions. The computer, for example may carry out drawing routines and the like. Accordingly, by locating the computer separately from the light, extremely powerful effects are enabled.

The present inventor noted a number of different problems in the system. First of all, during the control by the computer, a large number of operations and specifically numerical operations, each need to be carried out. Complex calculation may cause problems in the computer, and specifically may cause the computer to crash. If the computer crashes, the output will include an indication of the crash, e.g., a “blue screen” or equivalent. It would be extremely undesirable for such an indication to be shown by the projector during a show.

Another problem may be caused by fading effects. It is possible to cause fading effects on the computer by drawing the output from the computer at a lower intensity. However, as the drawn screen fades, it is more difficult for even the operator to see it on the monitoring screen. Moreover, after an image has been caused to fade, it cannot be replaced. Certain effects, such as so-called decay, in which the image is caused to repeatedly replaced, cannot be easily carried out with this system.

Accordingly, and even though the computer is quite capable of producing a dimmed-intensity image, the present system uses an external interface board 115 which carries out an analog based dimming on the digitally produced image.

[Interface 115 may have the general layout shown in block diagram form in FIG. 2.

FIG. 2 shows the computer 110 which operates as described further herein, but basically operates to produce an image whose output will drive a stage lighting device. The image may be produced using conventional computer graphics technique, and as described herein, this may use standard “open GL” components in order to draw an image in the video card.

The video card 200 of the computer is shown in FIG. 2. In an embodiment, this video card may draw the image at full intensity. The video output 205, which is a full intensity image is coupled to a video in connector 210. Video in connector is coupled to a first dimmer 215 and a second dimmer 220. These dimmers can be separately controlled so that the output on the operator's monitor display can be the same as or different from the output being viewed.

Video output connector 225 is connected to a video screen 231 which may form a monitor which allows a user to monitor the video output. Under computer control, the monitor screen 230 can either show a full intensity version of the output of the video card, or can show the actual dimmer version. Since the dimmers 215, 220 can be separately controlled, the operator can switch whether they see the dimmed version or the full intensity version.

The USB port 202 from the computer 110 is also connected to a corresponding USB input 230 on the dimmer board, which controls an onboard processor 242 to allow controlling the dimmers as described herein.

The dimmer 215 controls the intensity that is viewed by the operator locally. The dimmer 220 controls the output intensity. Again, however, this enables the video card 200 to output its video at full intensity, while still producing a dimmed version of the image as output to the light.

The computer 110 executes a routine described further herein. According to this routine, the output light 240 which will be seen on the projector is immediately faded to complete black whenever a control screen is being executed by the computer 110. In addition, the computer 110 must produce new dimmer outputs at each frame update, even if they are the same as the previous. The processor 242 on the dimmer board expects these updates at each frame. If the processor 242 does not receive these frame updates, it immediately commands the dimmer to fade to black.

The processor on the dimmer board operates according to the flowchart of FIG. 3. It should be understood, however, that processor 242 may carry out additional functions in addition to those described herein. At 300, the system receives a full brightness image. Of course, the image which is produce need not be full brightness. At 305, the system determines if it has received a new fade value for the current frame. If not, then an error has occurred in the computer, and the output of the dimmer 220, that draws the output screen, is set to black at 310. This prevents any kind of crash screen or control screen from being displayed as part of the show.

At 315, the system determines whether both the stage output and the monitor output have been commanded to dim. If so, then both dimmers are set to the controlled value at 320. If not, then only the output dimmer bank is set to the controlled value at 325.

This produces a number of advantages in which both the show attendees are prevented from seeing control screens, but also the operator can see a full brightness image. Further the video card can draw a full brightness image to allow certain effects.

A more detailed block diagram of the dimmer card is shown in FIG. 4. The USB connector 405 provides a control line which controls the operation of the dimmer card. The processor 400 drives the USB and receives commands from that card. The output of the processor drives a decay converter 410 which produces analog output voltages which are sent to each of six different analog multipliers 420-426. There are two different banks of analog multipliers. One bank of analog multipliers is to produce the output for the stage, and includes a multiplier for each of red, green and blue. The other analog multiplier bank is for the local monitor, and includes one analog multiplier for each of red green and blue, but drives the output for the local display.

A DMX 512 output may also be produced from a DMX serializer chip 430. This may be in output in conventional DMX-format which provides the states of the output of the dimmers in a timeslot multiplexed format.

Although only a few embodiments have been disclosed in detail above, other modifications are possible. All predictable modifications are intended to be encompassed within the following claims. 

1. A system, comprising: a first, computer system, including a video card, producing an output signal intended for driving a projector with an image, based on the control signal, and producing a second output signal, based on said control signal, indicative of a dim value of the output signal; and a second system, receiving said output signal, and said dim value, and operating to dim an intensity value of the output signal based on said dim value, to produce an output signal to be projected.
 2. A system as in claim 1, further comprising a lighting projector, receiving said output signal to be projected, and producing a projection output based thereon.
 3. A system as in claim 1, wherein said second system produces a second output signal intended for display on a monitor, having a dim value which is separately controlled from a dim value of the output signal to be projected.
 4. A system as in claim 1, wherein said second system includes a plurality of analog multipliers, controlled by said dim value.
 5. A system as in claim 4, wherein said dim value is produced over a USB connection.
 6. A system as in claim 4, further comprising a D/A converter, receiving said first output signal, and producing an analog version of said first output signal, said analog version connected to said plurality of analog multipliers.
 7. A system as in claim 3, further comprising a lighting projector, receiving said output signal to be projected, and producing a projection output based thereon, and further comprising a user interface monitor, receiving said second output signal, and producing a different output based on said second signal.
 8. A system, comprising: a controller part, which produces video information indicative of an image to be displayed; and a bank of dimmer devices, controlled by said controlling part, and coupled to receive said video information and to provide a dimming function for said video information to produce another output signal indicative of a dimmed version of said image.
 9. A system as in claim 8, wherein said bank of dimmer devices includes a first dimmer device for dimming red components of the video information, a second dimmer device for dimming green components of the video information, and a third dimmer device for dimming blue components of the dimmer information.
 10. A system as in claim 9, wherein each dimmer device in said bank of dimmer devices includes an analog multiplier which multiplies said information indicative of the image by a dim value.
 11. A system as in claim 8, further comprising a first dimmer part which produces a first dimmed version for display on a monitor screen, and a second dimmer port which produces dimming information separately for a display version.
 12. A system as in claim 8, wherein said the dimmer device monitors said controller part for errors, and immediately produces a maximum dimming when said errors are detected.
 13. A system as in claim 9, wherein said bank of dimmer devices monitors said controller part for errors, and immediately produces a maximum dimmed effect on said display version, but does not dim an output for said monitor screen to be viewed at normal intensity, when said errors are detected.
 14. A system as in claim 13, further comprising an output which produces information indicative of dimming in a format which is timeslot multiplexed.
 15. A system as in claim 11, further comprising, responsive to a command from said controlling part, dimming said display version while not dimming said monitor screen.
 16. A system as in claim 8, further comprising a universal serial bus link between said controller part and said bank of dimmer devices.
 17. A system, comprising: a first, controlling part, including a video card, producing an output signal indicative of an image, by drawing the output signal in the video card; and an external device, receiving information from said video card, and producing a first output for a monitor screen and a second output to be displayed, and monitoring for updates from said first controlling part, and preventing the output signal from being displayed on said display screen when said updates are not received for a specified time period.
 18. A system as in claim 17, wherein said outputs are indicative of an amount of dimming to be carried out by said external device for a current frame.
 19. A system as in claim 18, wherein said external device includes analog dimmers thereon.
 20. A system as in claim 19, wherein said video dimmers comprise analog multipliers, which multiply said output signal by a value, and includes a first multiplier which produces said first output and a second multiplier which produces a separately dimmed output for said second output display.
 21. A system as in claim 17, further comprising producing a serialized version of dimmer commands as an output signal.
 22. A system as in claim 17, wherein said first controlling part produces an image at full brightness, and produces output signals indicative of an amount of dimming to be carried out.
 23. A system as in claim 17, further comprising a controlling console, controlling a plurality of lamps which collectively form a light show, and producing output signals indicative of said control, one of said output signals being coupled to said first controlling part.
 24. A method, comprising: producing a digital representation of an image to be displayed on an external projector; and carrying out an analog dimming of the image prior to display on said external projector.
 25. A method, comprising: producing a request for an output image at less than full output intensity; drawing a full intensity output image in a video card; and carrying out a dimming operation on said full intensity output image.
 26. A system, comprising: an input for video signals; a plurality of analog multipliers, coupled to receive said video signal, said plurality of analog multipliers including a first multiplier set which produces a first viewable output, and a second multiplier set which produces a second, monitor output, a processor, also having an input for a control signal and which controls said first multiplier set separately from said second multiplier set; and first and second video outputs, said first video output receiving an output from said first multipliers said, and said second video output receiving said output from said second multiplier set.
 27. A system as in claim 26, further comprising a serializer, producing an output in a DMX 512 format.
 28. A system as in claim 26, wherein said control signal uses a USB format control signal.
 29. A system as in claim 26, wherein said processor monitors for control signals at specified intervals, ‘and automatically produces a dimmed output on said first multipliers set when said control signals are not received at said specified intervals. 